EFFECT OF SOLVENT COMPOSITION ON THE ELECTROCHEMICAL PERFORMANCE OF HIGH-VOLTAGE CATHODE LiNi0.5Mn1.5O4

The spinel LiNi0.5Mn1.5O4 (LNMO) is considered as an accurate cathode material for high-voltage Li-ions batteries above 4.5 V due to its high energy density, safety and eco-friendly. The electrochemical performance of spinel LNMO depends on the combability between electrode material and electrolyte. In this work, we reported the essential role of solvent compositions–carbonate solvents such as ethylene carbonate (EC), dimethyl carbonate (DMC), ethylene methyl carbonate (EMC)–in 1 M LiPF6 electrolytes on the long-term cycling test. The volumetric ratios in which the solvent compositions were varied were as follows: EC-EMC (7:3), EC-EMC (1:1), EC-DMC (1:1), EC-DMC (1:2). Result of cycling test in the solvent EC-EMC (7:3) leads to a discharge capacity of 140 mAh/g and a retention of 85 % initial capacity after 50 cycles.

MORE ENVIRONMENTAL FRIENDLY METHOD OF LEAD RECYCLING FROM WASTE BATTERY PASTE-AN ELECTROCHEMICAL INVESTIGATION

Joint Research on Environmental Science and Technology for the Eart

Kakvoća tjestenine bogate vlaknima, obogaćene prahom kore lubenice različitih veličina čestica

Research background. Watermelon rind, a by-product of watermelon juice processing, contains large amounts of dietary fibre and phenols with antioxidant capacity. The use of agro-industrial by-products would both improve economic benefits and reduce environmental emissions. The aim of this research is to examine the effect of the particle size of watermelon rind powder on the quality of high-fibre pasta. Experimental approach. The nutritional, physical and physicochemical quality of three samples of watermelon rind powder, sieved through three sieves with aperture size of 400, 210 and 149 μm, were analysed. Durum wheat semolina with watermelon rind powder mass fraction of 10 % were mixed and used to make pasta. Nutritional, textural and cooking quality, sensory acceptability, in vitro glycaemic index and antioxidant bioaccessibility of high-fibre pasta with added watermelon rind powder of different particle sizes were evaluated and compared. Results and conclusions. When the sieve aperture size was reduced from 400 to 149 µm, the soluble dietary fibre and total phenolic contents of watermelon rind powder were increased by 35 and 15 %, respectively, while its insoluble dietary fibre content was decreased by 21 %. Decrease in sieve aperture size from 410 to 149 µm reduced phenolic bioaccessibility of the fortified pasta from 63 to 57 %, but enhanced its predicted glycaemic index from 50 to 69. It also decreased the pasta hardness by 13 %, but improved its elongation rate and tensile strength by 13 and 40 %, respectively. The finer the particles of the watermelon rind powder, the longer the optimal cooking time, the higher the water absorption index, and the lower the cooking loss of the supplemented pasta. Consumers did not notice any significant differences in the overall acceptability among all pasta samples. Novelty and scientific contribution. The particle size of the watermelon rind powder had a major effect on nutritional value, texture and cooking quality of the fortified pasta. In particular, the predicted glycaemic index and antioxidant bioaccessibility of high-fibre pasta were significantly affected by the particle size of the dietary fibre material used in the recipe.Pozadina istraživanja. Kora lubenice, nusproizvod prerade soka lubenice, sadržava velike količine prehrambenih vlakana i fenola s antioksidacijskim svojstvima. Korištenjem agroindustrijskih nusproizvoda poboljšala bi se ekonomska učinkovitost procesa i smanjila emisija u okoliš. Svrha je ovog istraživanja bila ispitati utjecaj veličine čestica praha kore lubenice na kakvoću tjestenine bogate vlaknima. Eksperimentalni pristup. Ispitane su nutritivna, fizikalna i fizikalno-kemijska kakvoća triju uzoraka praha kore lubenice, prosijanih kroz tri sita veličine otvora 400, 210 i 149 μm. Krupica od durum pšenice pomiješana s 10 % praha kore lubenice upotrijebljena je za izradu tjestenine. Procijenjeni su i uspoređeni sljedeći parametri: nutritivna i teksturalna kakvoća te ona nakon kuhanja, senzorska prihvatljivost, in vitro glikemijski indeks i antioksidacijska biološka raspoloživost tjestenine bogate vlaknima s dodatkom praha kore lubenice različitih veličina čestica. Rezultati i zaključci. Smanjenjem veličine otvora sita s 400 na 149 µm povećali su se udjel topljivih prehrambenih vlakana za 35 % i ukupni udjel fenola u prahu kore lubenice za 15 %, dok se udjel netopljivih prehrambenih vlakana smanjio za 21 %. Smanjenjem veličine otvora sita s 400 na 149 µm smanjila se biološka raspoloživost fenola iz obogaćene tjestenine sa 63 na 57 %, ali se njezin predviđeni glikemijski indeks povećao s 50 na 69. Također se smanjila tvrdoća tjestenine za 13 %, no poboljšala se njezina rastezljivost za 13 % i vlačna čvrstoća za 40 %. Što su čestice praha kore lubenice bile sitnije, to je dulje bilo optimalno vrijeme kuhanja, veći je bio indeks upijanja vode i manji gubitak proizvoda nastao kuhanjem. Potrošači nisu primijetili nikakve bitne razlike u ukupnoj prihvatljivosti uzoraka obogaćene tjestenine. Novina i znanstveni doprinos. Veličina čestica praha kore lubenice uvelike je utjecala na nutritivnu vrijednost, teksturu i kakvoću obogaćene tjestenine nakon kuhanja. Konkretno, veličina čestica prehrambenih vlakana u materijalu korištenom u recepturi bitno je utjecala na predviđeni glikemijski indeks i antioksidacijsku biološku raspoloživost tjestenine bogate vlaknima

In vitro antioxidant activity and bioactive compounds from Calocybe indica

Nowadays, the use of mushrooms in medicine is ubiquitous and has achieved particular success. The antioxidants in mushrooms can deactivate free radicals. This study assesses the antioxidant potential of mushroom Calocybe indica with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging methods and the total antioxidant capacity. The mushroom’s ethanol extract exhibits acceptable activity with a low IC50 value (240.11 μg/mL), approximately 2.9 times lower than that of the mushroom Ophiocordyceps sobolifera extract. The ABTS scavenging rate of the extract is around 60% at 500 µg/mL, and the total antioxidant capacity is equivalent to 64.94 ± 1.03 mg of GA/g or 77.42 ± 0.42 μmol of AS/g.  The total phenolics, flavonoids, polysaccharides, and triterpenoids are equivalent to 29.33 ± 0.16 mg of GAE/g, 17.84 ± 0.11 mg of QUE/g (5.04 ± 0.04%), and 4.96 ± 0.04 mg of oleanolic acid/g, respectively. Specifically, the total triterpenoid content has been reported for the first time. The mushroom can have potential biomedical applications

Enzimatska obrada iskorištenih listića zelenog čaja i njihova primjena u proizvodnji čajnog peciva s velikim udjelom prehrambenih vlakana

Research background. By-products of food industry have been studied as sources of high fibre and antioxidant ingredients for healthy food products, because of their economic and environmental benefits. However, the soluble dietary fibre content of these materials is usually lower than the recommended value that is claimed to bring positive health effects. Enzymatic treatment could be an efficient method for modifying insoluble and soluble dietary fibre contents of these materials. The purpose of this study is to investigate the effects of enzymatic treatment conditions on soluble, insoluble and total dietary fibre mass fractions in spent green tea leaves, and evaluate the quality of dough and cookies when different mass fractions of untreated and treated leaves were added to the recipe. Experimental approach. The mass fractions of soluble, insoluble and total dietary fibre in spent tea leaf powder was evaluated after the leaves were treated with cellulase amount of 0−25 U/g for 0 to 2 h. Wheat flour was replaced by untreated and treated spent tea leaf powder at 0, 10, 20, 30 and 40% in cookie formulation. Textural properties of dough, proximate composition, physical properties and overall acceptability of cookies were analysed. Results and conclusions. The appropriate conditions for enzymatic treatment were enzyme loading of 20 U/g and biocatalytic time of 1.5 h, under which the mass fraction of soluble dietary fibre in spent tea leaves increased by 144.5% compared to that of the control sample. The addition of spent tea leaves led to the increase in dough hardness. Increase in the spent tea leaf amount also enhanced fibre mass fraction, antioxidant activity and hardness of cookies but reduced their overall acceptability. Moreover, the enzymatic treatment of spent tea leaves improved the soluble to total dietary fibre ratio of the cookies, which influenced their textural properties and health benefits. The cookies with added 20% untreated or treated spent tea leaves were overall accepted by the panel. Novelty and scientific contribution. For the first time, spent tea leaves have been treated with enzymes to improve their soluble to total dietary fibre ratio. The treated spent tea leaves are a new promising high-fibre antioxidant ingredient for cookie preparation.Pozadina istraživanja. Nusproizvodi prehrambene industrije ispituju se iz ekonomskih i ekoloških razloga kao izvori sastojaka s velikim udjelom prehrambenih vlakana i antioksidacijskim učinkom koji se mogu upotrijebiti u proizvodnji zdrave hrane. Međutim, udjel topljivih prehrambenih vlakana u nusproizvodima je obično manji od preporučenih vrijednosti koje mogu imati pozitivan učinak na zdravlje. Enzimatska obrada bi mogla biti učinkovita metoda modificiranja netopljivih i topljivih prehrambenih vlakana iz otpada prehrambene industrije. Svrha je ovog rada bila ispitati utjecaj različitih uvjeta enzimatske obrade na masene udjele topljivih, netopljivih i ukupnih prehrambenih vlakana u iskorištenim listićima zelenog čaja, te procijeniti kakvoću tijesta i čajnog peciva s dodatkom različitih masenih udjela obrađenih i neobrađenih listića. Eksperimentalni pristup. Maseni udjeli topljivih, netopljivih i ukupnih prehrambenih vlakana u prahu od iskorištenih listića zelenog čaja mjereni su nakon njihove obrade s 0–25 U/g celulaze tijekom 0 do 2 h. U smjesi za čajno pecivo je pšenično brašno zamijenjeno s 0, 10, 20, 30 i 40 % obrađenog ili neobrađenog praha iskorištenih listića zelenog čaja. Ispitani su tekstura tijesta te kemijski sastav, fizikalna svojstva i ukupna prihvatljivost dobivenog čajnog peciva. Rezultati i zaključci. Pri povoljnim uvjetima enzimatske obrade, a to su 20 U/g enzima i vrijeme trajanja biokatalitičkog procesa od 1,5 sata, maseni udjel topljivih prehrambenih vlakana u iskorištenim listićima zelenog čaja porastao je za 144,5 % u usporedbi s kontrolnim uzorkom. Dodatkom iskorištenih listića zelenog čaja povećala se tvrdoća tijesta. Povećanjem količine listića čaja povećali su se i maseni udjel vlakana, antioksidacijska svojstva i tvrdoća čajnog peciva, ali se smanjila njihova prihvatljivost. Osim toga, enzimatskom se obradom iskorištenih listića zelenog čaja poboljšao omjer topljivih i ukupnih vlakana u čajnom pecivu, što je utjecalo na njegovu teksturu i pozitivan učinak na zdravlje. Panel ocjenjivača je okarakterizirao čajno pecivo s dodatkom 20 % obrađenih ili neobrađenih iskorištenih listića čaja kao prihvatljive. Novina i znanstveni doprinos. Prvi put je enzimatskom obradom iskorištenih listića zelenog čaja poboljšan njihov omjer topljivih i ukupnih prehrambenih vlakana. Obrađeni iskorišteni listići zelenog čaja novi su obećavajući sastojak s antioksidacijskim svojstvima koji se može upotrijebiti u pripremi čajnog peciva

LAYERED O3-NaFe0.5Co0.5O2 AS HIGH CAPACITY AND LOW- COST MATERIAL FOR SODIUM ION BATTERIES

O3-NaFe0.5Co0.5O2 layered cathode material was synthesized by solid state reaction at 900 oC followed by a quenching step in argon atmosphere. The chemical composition and morphology of synthesized material were analyzed by Atomic Absorption Spectroscopy (AAS) and Scanning Electron Microscopy (SEM). The electrochemical properties were evaluated by Cyclic Voltammetry (CV) and charge-discharge cycling. The material NaFe0.5Co0.5O2 shows the sloped discharge curves with high flat voltage plateau and excellent cycling stability. The reversible capacity of about 120 mAh/g at rate C/10 and good capacity retention after 100 cycles were obtained

TiO 2

An improved photocatalytic activity of semiconductor materials using incorporation of the noble metals such as Ag, Au, and Pt is a promising technology. In this study, Ag nanoparticle-TiO2 nanotube structures (Ag-TNTs) have been investigated as a photocatalyst in different irradiation conditions using different characterization techniques. The results indicate that Ag nanoparticles dispersed uniformly on the TNTs’ surface without any change in TNTs’ morphology. In addition, Ag-TNTs exhibited lower photoactivity than the TNTs under UV irradiation. In contrast, Ag-TNTs increased the photoactivity in comparison with TNTs and the photocatalytic performance under sunlight irradiation. These phenomena could be contributed to the appearance of Ag nanoparticles on the nanotube surface

Usporedba enzimske i ultrazvučne ekstrakcije albumina iz praha kondicioniranih sjemenki bundeve (Cucurbita pepo)

In this study, ultrasound- and enzyme-assisted extractions of albumin (water-soluble protein group) from defatted pumpkin (Cucurbita pepo) seed powder were compared. Both advanced extraction techniques strongly increased the albumin yield in comparison with conventional extraction. The extraction rate was two times faster in the ultrasonic extraction than in the enzymatic extraction. However, the maximum albumin yield was 16 % higher when using enzymatic extraction. Functional properties of the pumpkin seed albumin concentrates obtained using the enzymatic, ultrasonic and conventional methods were then evaluated. Use of hydrolase for degradation of cell wall of the plant material did not change the functional properties of the albumin concentrate in comparison with the conventional extraction. The ultrasonic extraction enhanced water-holding, oil-holding and emulsifying capacities of the pumpkin seed albumin concentrate, but slightly reduced the foaming capacity, and emulsion and foam stability.U ovom su radu uspoređena dva postupka izolacije albumina, proteina topljivog u vodi, iz praha kondicioniranih sjemenki bundeve (Cucurbita pepo), i to ekstrakcijom pomoću ultrazvuka te pomoću enzima. U usporedbi s konvencionalnom ekstrakcijom, oba su postupka znatno povećala prinos albumina. Ultrazvučna je ekstrakcija bila dva puta brža od enzimske, međutim, najveći je prinos albumina od 16 % dobiven enzimskom ekstrakcijom. Ispitana su funkcionalna svojstva koncentrata albumina dobivenog iz sjemenki bundeve enzimskom, ultrazvučnom i konvencionalnom ekstrakcijom. Enzimska hidroliza nije utjecala na funkcionalna svojstva koncentrata albumina, za razliku od konvencionalne ekstrakcije. Ultrazvučnom su ekstrakcijom poboljšana svojstva zadržavanja vode i ulja te emulgiranja, a neznatno smanjena svojstva pjenjenja te stabilnost pjene i emulzije koncentrata albumina

TỔNG HỢP VÀ ĐẶC TRƯNG hydrogel glucomannan – poly(acrylic acid) NHẠY pH ĐỊNH HƯỚNG ỨNG DỤNG TRONG HỆ THỐNG PHÂN PHỐI 5-aminosalicylic acid CÓ KIỂM SOÁT

In this study, glucomannan-poly(acrylic acid) hydrogels were synthesized under different conditions. The hydrogels consist of glucomannan and acrylic acid and are crosslinked by N,N-methylene-bis-(acrylamide). The structure and morphology of the hydrogels were investigated by using Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). The swelling ratio, biodegradation and pH-sensitive properties, relationship between hydrogel swelling rate and 5-ASA adsorption-desorption capacity, influence of medium pH on 5-ASA desorption, and 5-ASA adsorption kinetics were studied. The swelling ratio of the synthesized hydrogel samples is 16.70–56.21 times. This ratio is low in the pH 1.0 media and increases significantly in the pH 7,4 media. The hydrogels are biodegradable in the presence of cellulase (400 U·mg–1) in a pH 7.4 phosphate buffer at 37 °C (69.8% after ten days; the cellulase concentration 1.5 g·L­–1). The hydrogels exhibit high adsorption and desorption capacities for 5-ASA. The adsorption kinetics follows the pseudo-first-order model. These hydrogels can be applied to smart drug delivery systems.Trong nghiên cứu này, hydrogel glucomannan-poly(acrylic acid) đã được tổng hợp ở các điều kiện khác nhau với mục đích ứng dụng vào hệ thống phân phối thuốc 5-amiosalicylic acid (5-ASA) có kiểm soát. Hydrogel được tạo thành từ glucomannan và acrylic acid với tác nhân liên kết N,N-methylene-bis-(acrylamide). Cấu trúc và hình thái của hydrogel được nghiên cứu bằng phổ hồng ngoại chuyển dịch Fourier (FT-IR) và kính hiển vi điện tử quét (SEM). Tỷ lệ trương nở, tính chất phân huỷ sinh học và nhạy pH, mối quan hệ giữa tỷ lệ trương nở của hydrogel và khả năng hấp phụ-giải hấp 5-ASA, ảnh hưởng của pH môi trường để khả năng giải hấp 5-ASA và động học hấp phụ 5-ASA đã được nghiên cứu. Kết quả cho thấy tỷ lệ trương nở của các mẫu hydrogel là 16,70–56,21 lần. Tỷ lệ trương nở của hydrogel thấp ở môi trường pH 1 và tăng lên đáng kể trong môi trường pH 7,4.  Cellulase (400 U·mg–1) trong môi trường đệm pH 7,4 ở 37 °C có khả năng phân hủy sinh học hydrogel (69,8% sau 10 ngày; nồng độ cellulase 1,5 g·L–1). Hydrogel có cả khả năng hấp phụ và giải hấp tốt 5-ASA. Động học quá trình hấp phụ tuân theo mô hình biểu kiến bậc 1. Đây là vật liệu có tiềm năng ứng dụng trong phát triển hệ thống phân phối thuốc thông minh